28 (link). Generation of
cell lines overexpressing FLAG-ALYREF. Wildtype ALYREF or mutant
ALYREFM-c+ΔdcDNA and a N-terminal 3xFlag tag were cloned into a lentiviral vector
backbone (Addgene plasmid #31485), yielding a plasmid containing pRRL-SFFV
3x-Flag-Aly/REF-p2a-mCherry. For an overexpression of ALYREF variants in
K562 THOC1-GFP overexpressing cells, lentiviral particles carrying the
3x-Flag-ALYREF constructs were generated using Lenti-X cells (Takara) by
polyethylenimine transfection (Polysciences) of the viral plasmid and helper
plasmids pCMVR8.74 (Addgene plasmid #22036) and pCMV-VSV-G (Addgene plasmid
#8454), according to standard procedures. THOC1-GFP overexpressing K562
(DSMZ) cells were infected at limiting dilutions and GFP and mCherry double
positive cells were isolated using a BD FACSAria III cell sorter (BD
Biosciences). Viral integration was confirmed by immunoblotting for ALYREF
(antibodies: Ancam ab202894 and Proteintech 16690-1-AP) and FLAG (A8592;
Sigma-Aldrich).